This invention relates to a self-propelled multi-terrain vertical lift transporter for lifting and transporting loads over various soil conditions and terrain.
Forklift trucks are widely used in a variety of applications and come in many different shapes and sizes. In particular, many forklifts have been designed especially for light duty applications. However, these light duty forklifts typically have a fixed wheel base making it difficult to use them in narrow passageways and at the same time lack the requisite stability to avoid tipping or overturning in response to unbalanced loads or encountering variable terrain.
U.S. Pat. No. 4,571,139 issued Feb. 18, 1986 to Moseley et al. discloses a freight handling truck comprising a frame mounted on at least three wheels, a supporting mast, lifting forks and a motor. Of the three wheels, at least one is a driving wheel powered by the motor and the other two wheels are idler wheels, mounted on two horizontally pivotal wheel arms. The pivotal wheel arms are powered by the motor to pivot them laterally to either widen or narrow their lateral extent. The pivotal wheel arms are also telescopic, allowing them to extend or retract. In the freight handling truck disclosed by Moseley et al. the wheels mounted at the ends of the adjustable wheel arms are not capable of pivoting or re-orienting as the wheel arms pivot. Therefore, the wheels mounted on the adjustable wheel arms are parallel with the path of travel of the device for only one angle of the wheel arms. Thus increased friction occurs when the angle of the wheel arms is changed to different angles. Also, the freight handling truck, as disclosed by Moseley et al., cannot lower a load to the floor if the pivotal wheel arms are in the narrowed position. The freight handling truck disclosed by Moseley et al. is further limited in that it is incapable of performing a tight radius turn.
It is, therefore, an object of this invention to provide a lift transporter with improved stability and maneuverability.
It is a further object of this invention to provided a lift transporter which is capable of laterally adjusting its wheel base.
It is a further object of this invention to provide a lift transporter capable of performing a tight radius turn.
It is a further object of this invention to provide a lift transporter which is reduced in weight.
The lift transporter of this invention is constructed of a steel frame which houses a motor and the hydraulic systems. Four wheels, two front and two rear, are mounted onto the frame. The two front wheels are mounted on laterally adjustable outriggers which are arranged outside of the lifting forks. The separation of the laterally adjustable outriggers, through the operation of the hydraulic systems, can be widened or narrowed as required. The two rear wheels are mounted on a common axle which is journaled to a post. Thus, the rear wheels are locked together for improved traction and are hydraulically powered. The front and rear wheels are of a sufficient width and tread design to allow the lift transporter to move over various terrain including gravel, sand and mud.
The lift platform of the lift transporter may consist of lifting forks, or other lifting implements, all of which can be interchanged simply by lifting one implement off of the horizontal members of the lift carriage and replacing it with another implement. The lift carriage is hydraulically powered to be raised and lowered.
The lift transporter is steered utilizing a tiller handle. Mounted to the neck of the tiller handle are the controls for raising and lowering the lift assembly, moving the lift transporter forward and reverse, and widening and narrowing the laterally adjustable outriggers. Also, the tiller handle and the rear wheel assembly are constructed to pivot through a wide range thereby allowing the lift transporter to perform tight radius turns.
The improved lift transporter of this invention does not require a counter weight as the center of gravity of any load is substantially within the wheels and thus cannot tip the unit.
Other objects and advantages of the invention will become clear from the following detailed description of the preferred embodiment, which is presented by way of illustration only and without limiting the scope of the invention to the details thereof.